The objectives of this project are to 1) identify the most meaningful predictors of mortality for mentally retarded persons, 2) to develop refined estimates of life expectancy for these people, 3) to examine the effect of health-related characteristics of residential settings on mortality, and 4) to determine the extent to which information on life expectancy can be useful to families and service systems. Previous studies of life expectancy have focused almost entirely on institutionalized groups of mentally retarded people, and have examined a limited number of predictor variables. Moreover, there has been no systematic examination of the stability of mortality rates over an extended period of time. Although much attention has been focused on the practical and psychological concerns of families of mentally retarded individuals, we have not found any evidence in the literature that the issue of life expectancy has been addressed. In addition to providing more accurate estimates of life expectancy than are currently available, the proposed project will examine the potential uses and benefits of this information for family planning and efficient service delivery.